Low severity · published Apr 2, 2026
CVE-2026-35388
OpenSSH before 10.3 omits connection multiplexing confirmation for proxy-mode multiplexing sessions
2.5
CVSS
0.1%
EPSS
No
On KEV
Description
OpenSSH before 10.3 omits connection multiplexing confirmation for proxy-mode multiplexing sessions.
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N
Attack vector
Local
Complexity
High
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 3% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
OpenSSH · OpenBSD
before 10.3 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-35388
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-35388
Third Party Advisory
https://marc.info/?l=openssh-unix-dev&m=177513443901484&w=2
Release Notes
https://www.openssh.org/releasenotes.html#10.3p1
Third Party Advisory
https://www.openwall.com/lists/oss-security/2026/04/02/3
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